I can make new portals to provide examples, but functionally its wherever the first portal is built in the overworld and generated in the nether.  No matter.
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The only way I can get the portal generation to work is by unloading the chunks by tping/traveling.
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(added image that shows the portal list from the game files as of 12/25) I had to make all of them by hand in order for them to link, All new portals are defaulting to 1579,226 and it's matching nether location. Â
closing as lag related - staying on the other side of the portal for a few extra seconds and the piglin did end up coming over 😞